The revival of interest in coal-fired power plants, notably in the USA, is showing no signs of abating, and indeed every sign of accelerating. This is not at all surprising in view of the USA’s present generating capacity problems and the wide cost differential that has now developed between coal and its upstart rival, natural gas, which is currently about four times as expensive. All the talk about a resurgence in coal is beginning to turn into some solid plant orders, with no less than 15 new coal plants announced in the first couple of months of 2001.
Recently, B&W won what it sees as a very significant contract, for something that has become rather rare in the USA of late: a new power station running on pulverised coal. Wygen 1 (see pp 26-27) is a mere 80 MWe in capacity. But when the order was placed it was billed as the only pulverised coal power plant currently on order in the USA. However, this may change in the near future. The owner of Wygen 1, Black Hills Corp, is looking to add another 500 MWe of new coal generating capacity.
In the circulating fluidised bed business, there are several coal projects underway in the USA and here too prospects look to be improving. Alstom, for example, has just reported the clinching of a substantial contract with Reliant for a 520 MWe CFB at Seward. Overall, it has been estimated that orders for new coal-fired generation in the United States could rise to 10 000 MWe per year by 2005.
One byproduct of this projected coal boom, juxtaposed with ever tightening environmental regulations, will be a burgeoning market for emissions control technologies, in particular flue gas desulphurisation (FGD), NOx reduction, particulates removal and, the new kid on the block, mercury control. This follows the US EPA’s recent pronouncement that, as expected, it will indeed take action to regulate mercury emissions at coal stations, prompting a flurry of development work on technologies which can address the issue.
In the case of FGD, a new report from the McIlvaine Company (see this month’s news) projects a doubling of the world market by 2006, to $ 6 billion, with the US share going from 18 per cent to 50 per cent. Against this backdrop, it comes as no surprise to learn that US company Foster Wheeler has just acquired the rights to sell the aqueous-ammonia-based FGD technology of German company Lurgi Lentjes. The latter’s process has the advantage that its byproduct is ammonium sulphate fertilizer as opposed to the calcium/sulphur-based waste product from conventional limestone-fed wet/dry FGD scrubbers, which often requires landfill disposal.
The Asian market for coal plant emissions reduction technology also looks substantial. China’s new five year plan (2001-2005), for example, talks about the need "to place special emphasis on the development and utilisation of clean coal technology." Meanwhile in Europe, a much clearer picture of what emissions levels the EU is looking for from power plant operators should emerge shortly. The long awaited EU directive on limiting SO2, NOx and particulate emissions from large combustion plants – the Large Combustion Plants Directive – will be finalised in the next six months. This covers plants above 50 MWt, including gas turbine units as well as coal stations. There are around 2000 such plants in the EU and they account for over 60 per cent of all sulphur dioxide emissions and over 20 per cent of NOx emissions within the region.
The new directive revises and updates the existing directive, which dates back to 1988, to reflect increased environmental concerns and the availability of better emissions control technologies. It covers three categories of plant: "existing plants", licensed before 1 July 1987, "old new plants", licensed after 1 July 1987 and before the entry into force of the new directive, and "new new plants", licensed after the entry into force of the new directive.
During 2000, after lengthy negotiations, the Commission and the Council of Environment Ministers agreed what is called a "Common Position" on the proposed revision of the directive, which was then placed before the European parliament. On 14 March the parliament voted in favour of a number of amendments to the draft directive, which could be described as ambitious or draconian, depending on your point of view. These would have the effect of considerably tightening the emissions requirements, but, say the critics, achieve only marginal environmental benefits, particularly in view of parallel directives addressing air quality and acidification. Their enactment could lead to early closure of a number of older coal plants.
Under EU procedures what happens now is a process called "Conciliation", which is intended to result in realistic compromises being reached and a final reading of the new directive, perhaps in September.
Whatever the details finally agreed the new directive will form part of the tightening emissions regime that power plants must contend with, which also includes the existing domestic legislation of the various EU countries as well as other EU directives. Meeting this additional regulatory burden will be a challenge for the power plant community but presents further interesting opportunities for developers and suppliers of emissions reduction technologies.
How much electricity does the internet use?
Eight per cent has become widely accepted as the share of electricity consumed by the Internet in the United States. The number comes from a 1999 report by Mark Mills, sponsored by a body called the Greening Earth Society, for which he acts as science advisor. The report also suggested that electricity consumption attributable to the Internet could grow to half of all electricity consumption over the next two decades.
Although it seems astonishingly high, the 8 per cent figure has been widely quoted, and has been elevated to the status of conventional wisdom. However, a new study by the US DoE’s Lawrence Berkeley Laboratory has concluded that the Mills estimate is about a factor of eight too high. Perhaps it was wishful thinking. The Greening Earth Society was set up by Western Fuels Association to promote fossil fuel use and the unfashionable message that "CO2 is beneficial to humankind and all of nature."